To date, 68 healthy volunteers were accrued as active granulocyte donors and donated a total of 162 filgrastim- and dexamethasone-stimulated granulocyte apheresis components. These were administered to 25patients with severe neutropenia and life-threatening infections; the most common recipient diagnosis was severe aplastic anemia (n=11), followed by chronic granulomatous disease (n=8), acute leukemia (n=3) and non-Hodgkins lymphoma (n=1). Nine of 25 recipients had disseminated mold and 16 had life-threatening bacterial infections, including two with carbapenem-resistant Klebsiella pneumonia. A median of 4 granulocyte transfusions (range 1 to 41) were administered per patient course. Five patients did not respond to the granulocyte transfusions (GTX) and died rapidly, one assessed as a futile effort, and the other unable to receive a sustained course of GTX due to HLA alloimmunization and lack of compatible donors. The remaining 20 showed stability or clinical improvement, although 7 later died due to their underlying disease. Fourteen of 25 were discharged from hospital. One recipient developed HLA alloimmunization due to GTX, which resulted in rejection of an unrelated cord blood graft. Donors experienced mild to moderate insomnia, nightmares, irritability and jitteriness related to the dexamethasone, and myalgia, arthralgias, fatigue and flushing related to the filgrastim administration. Thirty-one donors underwent comprehensive eye exams for cataract detection as a baseline assessment prior to repetitive dexamethasone administration. Donor retention in the program was 79%, with donor loss due to moving away from the Bethesda area or loss of interest. A mean of 7.4 liters were processed per procedure, during which 7.26 x 10e10 granulocytes (range 3.49-20.61 x 10e10) were collected in a volume of 326 mL. Granulocyte collection efficiency was only 44% using the Spectra apheresis device, with WBC differential composed of 89% granulocytes, and with a mean hematocrit of 12% and a mean red cell content of 39 mL.